1. Field of the Invention
The present invention relates generally to microscopes, and more particularly, to optical microscopes, confocal microscopes, fluorescence microscopes and spectral microscopes.
2. Prior Art
There has been a growing demand in recent years for scanning microscopes and confocal microscopes that afford scanning and imaging at high speed. Although hitherto disclosed microscopes include a disk scanner microscope (U.S. Pat. No. 5,717,519) in which the process of tandem scanning is improved and in which, for example, a lens array is employed, using this method, the alteration of the pinhole diameter is difficult and the setting of the optimum confocal pinhole diameter within the objective lens is very difficult. Additionally, in this method, the adjustment and centering of a plurality of pinholes and lens array is technically difficult. In addition, although, for a sample body in which there is extensive scattering, single-point scanning of the sample body can improve the contrast of the image, the process of changeover from multiple-point scanning to single-point scanning is very difficult.
In addition, although a method for producing an image by the scanning of an array comprising a plurality of focal points in a small range and a method for producing an image in which a plurality of linear laser beams are scanned over a small range have been disclosed (U.S. Pat. No. 6,028,306), using these methods, the adjustment and centering of a plurality of pinholes and lens array is technically difficult. In addition, because a large number of pinholes are present on the entire surface in the field of view, there are times when, in the observation of a sample body that is thick and has extensive scattering, the contrast of the image is reduced due to the scattering of the sample body. In addition, although, for a sample body in which there is extensive scattering, single-point scanning of the sample body can raise the contrast of the image, the process of changeover from multiple-point scanning to single-point scanning is very difficult.
Furthermore, a line scanning confocal microscope described in the Handbook of Biological Microscopy Second edition Chapter 25, page 406, FIG. 2(b), has been disclosed and although, using this method, because a line scanner is employed, the confocal effect is increased only in the X direction or Y direction at one side of the image, because the confocal effect is lowered on the opposing side, the resolution is lower than for a single-point or multiple point confocal microscope. In addition, the implementation of line sequence scanning in which the scanning excitation wavelength is altered for each wavelength is very difficult. In addition, the magnification cannot be altered easily without the employment of a relay system and, furthermore, the setting of the optimum scanning speed for the sample body is difficult.
In addition, although a two-photon microscope has been disclosed in which an MMM (Multi-focal Multi-photon Microscopy, Stefan W. Hell, U.S. Pat. No. 6,262,423) is employed, the microscope of this configuration does not comprise a confocal aperture. In addition, because the adoption of a configuration in which a confocal aperture is inserted into the microscope is difficult, the improvement of this method by the production of a confocal point is very difficult.
In addition, although a video rate scanning microscope has been disclosed in which an AOTF (Acousto-Optical Tunable Filter) is employed (U.S. Pat. No. 4,893,008), aberrations are produced when this microscope is used due to the effect of the AOTF on the laser beam itself which ejects the AOTF. As a result, there are times when the resolution is inferior to that of a point scanning-type laser scanning optical microscope.
In addition, in point scanning-type laser scanning microscopes that employ a galvanometer mirror such as that disclosed in the Handbook of Biological Microscopy Second edition Chapter 9, pages 139-154, because the sample body cannot be scanned at a plurality of points and the galvanometer mirror cannot be shaken at high speed, the scanning speed is very slow.
In addition, although scanning microscopes that use a resonance galvano have previously been disclosed, the scanning speed cannot be freely controlled using a resonance galvano. This is a particular difficulty even when the scanning is slow and even when the photometry position is fixed for the implementation of the photometry of a single-point light.
In addition, hitherto devised single-point scanning confocal microscopes as disclosed in U.S. Pat. No. 6,069,734 cannot accommodate objective lens of large pupil diameter. To accommodate lens of this type a galvanometer mirror comprising a mirror of large diameter must be adopted but, because the scanning of a large diameter galvanometer mirror at high speed is very difficult, the actualization of high speed scanning has, to this point, proven difficult.
Although micro-mirrors are employed in the present invention, the confocal image projected on to the photo detector which is, strictly speaking, a point light, dot light or line-shaped light rather than a two-dimensional image, does not constitute a two-dimensional image. To that end, the present invention is fundamentally different to the methods of observation that employ a DMD such as that disclosed in U.S. Pat. No. 5,597,832, U.S. Pat. No. 5,923,466 and U.S. Pat. No. 6,038,067).